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MEMCACHED_STAT_GET_VALUE(3) libmemcached-awesome MEMCACHED_STAT_GET_VALUE(3)

NAME

memcached_stat_get_value - libmemcached Documentation

Get memcached statistics

SYNOPSIS

#include <libmemcached/memcached.h>
Compile and link with -lmemcached


pointer to the memcached_instance_st being stat'ed
the current key
the length of the key without any terminating zero
the value read
the length of the value without any terminating zero
pointer to the user supplied context
memcached_return_t indicating success


  • ptr -- pointer to an initialized memcached_st struct
  • args -- particular state object to query
  • error -- pointer to memcached_return_t indicating success

array of memcached_stat_st objects for all available servers


  • stat -- pointer to a memcached_stat_st struct to fill
  • args -- particular state object to query
  • hostname -- the hostname or IP address of the server to stat
  • port -- the port of the server to stat

memcached_return_t indicating success


  • ptr -- pointer to initialized memcached_st struct
  • stat -- pointer to initialized memcached_stat_st struct
  • key -- the statistic to query
  • error -- pointer to memcached_return_t indicating success

string value of the statistic


  • ptr -- pointer to initialized memcached_st struct
  • stat -- pointer to initialized memcached_stat_st struct
  • error -- pointer to memcached_return_t indicating success

array of default keys probably available in the statistics


  • ptr -- pointer to initialized memcached_st struct
  • args -- particular state object to query
  • func -- memcached_stat_fn callback
  • context -- pointer to user supplied context

memcached_return_t indication success


DESCRIPTION

libmemcached has the ability to query a memcached(1) server (or collection of servers) for their current state. Queries to find state return a memcached_stat_st structure. You are responsible for freeing this structure. While it is possible to access the structure directly it is not advisable. memcached_stat_get_value() has been provided to query the structure.

memcached_stat_execute() uses the servers found in memcached_stat_st and executes a "stat" command on each server. args is an optional argument that can be passed in to modify the behavior of "stats". You will need to supply a callback function that will be supplied each pair of values returned by the memcached server.

memcached_stat() fetches an array of memcached_stat_st structures containing the state of all available memcached servers. The return value must be freed by the calling application. If called with the MEMCACHED_BEHAVIOR_USE_UDP behavior set, a NULL value is returned and the error parameter is set to MEMCACHED_NOT_SUPPORTED.

memcached_stat_servername() can be used standalone without a memcached_st to obtain the state of a particular server. "args" is used to define a particular state object (a list of these are not provided for by either the memcached_stat_get_keys() call nor are they defined in the memcached protocol). You must specify the hostname and port of the server you want to obtain information on.

memcached_stat_get_value() returns the value of a particular state key. You specify the key you wish to obtain. The key must be null terminated.

memcached_stat_get_keys() returns a list of keys that the server has state objects on. You are responsible for freeing this list.

A command line tool, memstat, is provided so that you do not have to write an application to do this.

RETURN VALUE

Varies, see particular functions.

Any method returning a memcached_stat_st expects you to free the memory allocated for it.

SEE ALSO

memcached(1) libmemcached(3) memcached_strerror(3)

March 6, 2023 1.1